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Study of OPNET and performance evaluation of WiMAX network under various path loss and terrain conditions in OPNET Anindita Kundu Suman Bhunia School of Mobile Computing and Communication Jadavpur University, Kolkata -32. overview. Introduction Path Loss and Path loss models OPNET
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Study of OPNET and performance evaluation of WiMAX network under various path loss and terrain conditions in OPNET Anindita Kundu Suman Bhunia School of Mobile Computing and Communication Jadavpur University, Kolkata -32
overview • Introduction • Path Loss and Path loss models • OPNET • Network Setup • Results • Conclusion
Introduction • WiMAX network is chosen for simulation as it promises to deliver high speed broadband internet connectivity for mobile users with high coverage area. • VoIP is expected to be the communication medium of the next generation and FTP is one of the most popular data transfer application. • OPNET is expected to provide us with comprehensive development environment and provide real life environment. • Our target is to verify the performance of the path loss models over a WiMAX network using a real time simulator, OPNET.
What is Path Loss? • Path loss is the reduction in power density or attenuation of an electro magnetic wave as it propagates through space. • Path loss may be due to many effects like free space path loss, refraction, diffraction, reflection and absorption. • Path loss is also influenced by terrain contours, environment (urban or rural), propagation medium (dry or moist air), distance between transmitter and receiver, and height and location of antennas.
Path Loss Models • Free Space – no or very little obstruction • Suburban Fixed • Terrain Type A – hilly terrain with moderate to high tree density. • Terrain Type B – mostly flat terrain with moderate to heavy tree density or a hilly terrain with light tree density. • Terrain Type C – flat terrain with light tree density. • Outdoor to Indoor and Pedestrian – small cells, low transmission power, low BS height, pedestrians on street or inside buildings. • Vehicular – larger cells, high transmission power, vehicular mobility.
WHY OPNET? • GUI for topology design which allows for realistic simulation of networks and has performance data collection and display module. • It has been used extensively and there is wide confidence in the validity of results it provides. • OPNET provides effective implementation of WiMAX technology modules.
End Simulation Methodology Start Understanding your goals and aspects for the Simulation Specifying the System Model Understanding the System Defining input and output NO NO Results sufficiently detailed System Results accurate YES Results Statistically useful YES Choosing inputs and running simulation YES NO
The 3-tiered OPNET Hierarchy • Three domains: Network, node, and process • Node model specifies object in network domain • Process model specifies object in node domain
Node Domain • Basic building blocks (modules) include processors, queues, and transceivers • Processors are fully programmable via their process model • Queues also buffer and manage data packets • Transceivers are node interfaces • Interfaces between modules • Packet streams • Statistic wires
Process Domain • Process model components • State transition diagrams • Blocks of C code • Kernel Procedures • State variables • Temporary variables • A process is an instance of a process model • Processes can dynamically create child processes • Processes can respond to interrupts
Conclusion • OPNET Modeler provides us with a real life simulation environment • Path loss value varies with the amount of reflection in the communicating path. • The reduction in Line-Of-Sight due to the terrain model of any area • decreases network throughput due to increase in attenuation and diffraction losses • increases packet end to end delay by causing nodes to re-initiate network registration more frequently under fluctuating cell coverage.
acknowledgement We deeply acknowledge the support from DST, Govt. of India for this work in the form of FIST 2007 Project on “Broadband Wireless Communications” in the Department of ETCE, Jadavpur University.
References • Aphiraksatyakul,D., Boon-Chong Seet, Chiew-Tong Lau, “Evaluation of Terrain Effects on Mobile WiMax in a Vehicular Environment”,ITS Telecommunications 2008, pp.379-383, October 2008. • Jeich Mar, Chin-Chung Ko, Chung-Haw Li and Shao-En Chen, “CELL PLANNING AND CHANNEL THROUGHPUT OF MOBILE WiMAX AT 2.5 GHz”, vol. 32, No. 5, Journal of the Chinese Institute of Engineers, 2009, pp.585–597. • N.Nagarajan' , Rajeev, B. Kaarthick, “Performnance analysis of Video Conferencing and Multimedia application Services over WiMAX”, IEEE International Advance Computing Conference (IACC 2009), Patiala, India, 6-7 March 2009 • G. Chu, D.Wang, S. Mei, “A QoS Architecture for the MAC protocol of IEEE 802.16 BWA System,” IEEE 2002 ICC, Circuits and Systems, vol. 1, July 2002, pp. 435 -439. • V.Erceg et al., “An Empirically Based Path Loss Model for Wireless Channels in Suburban Environments”, IEEE JSAC, vol. 17, July 1999, pp. 1205-1222. • OPNET Documentation. http://www.opnet.com • Xinjie Chang. Network simulations with OPNET. In Winter Simulation Conference, pages 307-314, 1999. • Iti Saha Misra, “Wireless Communications and Networks 3G and beyond”, Tata McGraw Hill Education Private Limited, 2009, New Delhi. • ITU-R, M.1225 “GUIDELINES FOR EVALUATION OF RADIO TRANSMISION TECHNOLOGIES FOR IMT-2000”
Network Setup The path loss models are selected from the drop down menu